The video game developer and publisher Sega produced home video game consoles and handheld consoles. These systems were released from the third console generation to the sixth. The first Sega console was the Japan-only SG-1000, released in 1983. Sega released several variations of this console in Japan, the third of which, the Sega Mark III, was rebranded as the Master System and released worldwide in 1985. They went on to produce the Genesis—known as the Mega Drive outside of North America—and its add-ons beginning in 1988, the Game Gear handheld console in 1990, the Sega Saturn in 1994, and the Dreamcast in 1998. Sega was one of the primary competitors to Nintendo in the video game console industry. A few of Sega's early consoles outsold their competitors in specific markets. Several of the company's later consoles were commercial failures, however, and the financial losses incurred from the Dreamcast console caused the company to restructure itself in 2001. As a result, Sega ceased to manufacture consoles and became a third-party video game developer. (Full list...)